This invention relates to portable shelter assemblies and, more particularly, to collapsible and expandable portable shelter assemblies.
In my prior U.S. Pat. Nos. 3,968,808, 4,026,313, 4,290,244, 4,437,275, U.S. Pat. No. Re. 33,710, and U.S. Pat. No. 5,230,196 I have disclosed interconnected pentagonal, hexagonal, rectangular, or square sections or modules for forming collapsible and expandable portable shelters. The shelters formed by these modules are light in weight and adapted to be quickly put up and taken down. The modules and shelters formed from the modules disclosed in, for example, my U.S. Pat. Nos. 3,968,808 and U.S. Pat. No. Re. 33,710 are self-supporting by virtue of a self-locking action resulting from the asymmetrical disposition of certain strut members forming the modules. While the self-locking aspect of these shelters is highly advantageous in facilitating the fast and simple erection of such shelters, it is desirable to provide a shelter having greater resistance to adverse conditions, such as wind or snow, which tend to create stresses in the structures.
My U.S. Pat. No. 5,230,196 provides a system including modules formed of pivotably pinned pairs of struts arranged on the sides of the modules. The strut pairs are pivotably attached to engageable and disengageable locking devices defining corners of the modules. When the locking devices are disengaged, the modules are adapted to fold into a bundle. When the modules are unfolded, the locking devices are manually engaged to form the expanded modules. The expanded modules including manually engaged locking devices exhibit enhanced resistance to stress-inducing conditions.
It is desirable to provide collapsible and expandable modules for forming portable shelters that are light in weight, and that exhibit great resistance to stress-inducing conditions. It is further desirable to provide expandable and collapsible modules for forming portable shelters that are adapted to be quickly put up at a site without tools, and are adapted to be put up by workers at ground level, without the need for ladders, or other similar equipment. It is further desirable to provide a portable shelter that is easy to store and transport. It is further desirable to provide a set of expandable and collapsible modules that are adapted to be combined in a variety of ways to form a variety of different types of portable shelters. It is still further desirable to provide expandable and collapsible modules for forming self-supporting portable shelters requiring no internal obstructions. It is still further desirable to provide expandable and collapsible modules of one or more types that possess sufficient strength to be combined with one another to form various types and sizes of portable shelters.